Mobile station, and apparatus, system and method for management of emergency calls

Abstract

The invention comprises emergency call management apparatus ( 31 ) and a mobile station ( 1 ). The emergency call management apparatus ( 31 ) monitors the emergency call generation rate, which is indicative of the rate of generation of emergency calls in a network, and on the basis of the result of this monitoring, transmits state information indicative of the restriction state of communication in that network, when the emergency call generation rate attains a preset condition. The mobile station ( 1 ) has emergency number information indicative of a number to be dialed to make an emergency call, and transmits, on the basis of the emergency number information and the received state information, a connection request to the network when the restriction state is a state in which only that emergency call is accepted and the number that has been dialed is the number to be dialed to make that emergency call. This provides a higher probability that an emergency call will be processed in situations in which there is a high rate of generation of emergency calls. This is because in such situations the network only has to process emergency calls.

What is claimed is:  
     
         1 . A mobile station comprising: 
 a storage part for storing state information indicative of the restriction state of communication in a network, and emergency call information indicative of a number to be dialed to make an emergency call; and    a control part for controlling, on the basis of said state information and said emergency call information, the transmission of a connection request to said network when said restriction state is a state in which only said emergency call is accepted and the number that has been dialed is the number to be dialed to make said emergency call.    
     
     
         2 . A mobile station as claimed in  claim 1 , wherein: 
 there are a plurality of items of said emergency call information;    each of said plurality of emergency call information items includes emergency rank information expressive of one of a plurality of ranks associated with the corresponding number to be dialed;    said state information contains state rank information indicative of rank and corresponding to said restriction state; and    said control part controls, on the basis of said state rank information and said emergency rank information, the transmission of a connection request to said network when the rank indicated by the emergency rank information associated with said number that has been dialed is greater than the rank indicated by said state rank information.    
     
     
         3 . A mobile station as claimed in  claim 1  or  2 , further comprising a display part; and wherein: 
 said storage part also stores a message serving to give notification of said state information; and  
 said control part outputs said message to the display part on the basis of said state information and said emergency call information when said restriction state is a state in which only said emergency calls are accepted and the number that has been dialed is not a number to be dialed to make a said emergency call.  
 
     
     
         4 . An emergency call management apparatus comprising: 
 a monitoring part for monitoring the emergency call generation rate, which is indicative of the rate of generation of emergency calls in a network; and    a management and control part for outputting, on the basis of the result of said monitoring, state information indicative of the restriction state of communication in said network, when said emergency call generation rate attains a preset condition.    
     
     
         5 . The emergency call management apparatus claimed in  claim 4 , wherein said restriction state is a state in which only said emergency calls are accepted.  
     
     
         6 . The emergency call management apparatus claimed in  claim 4  or  5 , further comprising a condition database for storing, as mutually correlated items, said preset condition for said emergency call generation rate, and said restriction state.  
     
     
         7 . An emergency call management system comprising: 
 an emergency call management apparatus for monitoring the emergency call generation rate, which is indicative of the rate of generation of emergency calls in a network, and for transmitting, on the basis of the result of said monitoring, state information indicative of the restriction state of communication in said network, when said emergency call generation rate attains a preset condition; and    a mobile station having emergency number information indicative of numbers to be dialed to make an emergency call, and which transmits, on the basis of said emergency number information and said state information that has been received, a connection request to said network when said restriction state is a state in which only said emergency calls are accepted and the number that has been dialed is a number to be dialed to make a said emergency call.    
     
     
         8 . A method for management of emergency calls comprising: 
 a step wherein a switch monitors the emergency call generation rate which is indicative of the rate of generation of emergency calls in a network;    a step wherein said switch outputs to a mobile station, on the basis of the result of said monitoring, state information indicative of the restriction state of communication in said network, when said emergency call generation rate attains a preset condition; and    a step wherein said mobile station, on the basis of said state information and emergency number information indicative of preset numbers to be dialed to make emergency calls, transmits to said switch a connection request containing information indicative of a said emergency call, when said restriction state is a state in which only emergency calls are accepted and the number that has been dialed is a number to be dialed to make a said emergency call.    
     
     
         9 . The method for management of emergency calls claimed in  claim 8 , further comprising: 
 a step wherein said switch, on the basis of said connection request, outputs to said mobile station information permitting connection of said mobile station; and    a step wherein said mobile station, on the basis of said information permitting connection, transmits to said switch information containing information indicative of said emergency call.    
     
     
         10 . A program for the purpose of executing on a computer a method comprising: 
 a step of monitoring the emergency call generation rate which is indicative of the rate of generation of emergency calls in a network;    a step of outputting to a mobile station, on the basis of the result of said monitoring, state information indicative of the restriction state of communication in said network, when said emergency call generation rate attains a preset condition;    a step of receiving a connection request containing information indicative of an emergency call, said connection request having been output by said mobile station in response to said state information; and    a step of outputting to said mobile station, on the basis of said connection request, information permitting connection of said mobile station.    
     
     
         11 . A program for the purpose of executing on a computer a method comprising: 
 a step of receiving, from a switch, state information indicative of the restriction state of communication in a network;    a step of determining, on the basis of said state information and emergency number information indicative of preset numbers to be dialed to make emergency calls, when said restriction state is a state in which only said emergency calls are accepted, whether or not the number that has been dialed is a number to be dialed to make a said emergency call; and    a step of transmitting, to said switch, a connection request containing information indicative of a said emergency call, when said dialed number is a number to be dialed to make a said emergency call.